ci: github pages deployment (#325)

Adds workflows/deploy_docs.yml to help automate reference website publishing.

Author: jooohhn

.github/workflows/deploy_docs.yml

@@ -0,0 +1,65 @@
+name: Publish documentation on GitHub Pages
+
+on: workflow_dispatch
+
+jobs:
+  authorize: 
+    name: Authorize
+    runs-on: ubuntu-18.04
+    steps:
+      - name: ${{ github.actor }} permission check to do a release
+        uses: octokit/request-action@v2.0.0
+        with:
+          route: GET /repos/:repository/collaborators/${{ github.actor }}
+          repository: ${{ github.repository }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  gh-pages:
+    name: Publish to GitHub Pages
+    runs-on: ubuntu-18.04
+    needs: [authorize]
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+
+      - name: node_modules cache
+        uses: actions/cache@v2
+        with:
+          path: '**/node_modules'
+          key: ${{ runner.os }}-modules-${{ hashFiles('**/yarn.lock') }}
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v1
+        with:
+          node-version: 10.x
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile && yarn docs:install --frozen-lockfile
+
+      - name: Generate website assets
+        run: yarn docs:generate-jsdoc
+
+      - name: Add key to allow access to repository
+        env:
+          SSH_AUTH_SOCK: /tmp/ssh_agent.sock
+        run: |
+          mkdir -p ~/.ssh
+          ssh-keyscan github.com >> ~/.ssh/known_hosts
+          echo "${{ secrets.GH_PAGES_DEPLOY }}" > ~/.ssh/id_rsa
+          chmod 600 ~/.ssh/id_rsa
+          cat <<EOT >> ~/.ssh/config
+          Host github.com
+          HostName github.com
+          IdentityFile ~/.ssh/id_rsa
+          EOT
+
+      - name: Release to GitHub Pages
+        env:
+          USE_SSH: true
+          GIT_USER: amplitude-sdk-bot
+        run: |
+          git config --global user.email "amplitude-sdk-bot@users.noreply.github.com"
+          git config --global user.name "amplitude-sdk-bot"
+          yarn docs:deploy